Some of Ireland’s most significant public health issues were addressed between 1939 and 1955 and yet this period, beyond neutrality and supply politics, has received little historical attention. Despite Ireland’s neutrality during the Second World War (1939-45), the war created a severe economic squeeze situation. Examining health policy, and negotiations about policy reveals where the pressure points were. This thesis examines five case studies, chosen due to their significance in government action: 1. Fortification of flour with calcium 2. Rise in diarrhoea and enteritis among infants 3. Implementation of the national nutrition survey 4. Introduction of the Mental Treatment Act 1945 5. New measures to combat tuberculosis While historiography identifies this period as a crucial turning point for addressing infant mortality, mental illness, infectious disease and to a lesser extent, malnutrition, these accounts often overlook that consecutive Irish governments were not singularly focused on any health problem alone during the Emergency period. Studies focusing on diseases often appear in isolation, thus missing the importance of the interaction between initiatives occurring at the same time with many of the same people involved. Contrary to stand-alone histories on individual diseases in Ireland, this thesis demonstrates that Ireland experienced health crises across all these areas. More babies died in Ireland during the war than before. Families also experienced food measures that fundamentally impacted their nutrition. Raising flour extraction rates stretched flour supplies but contributed to a rickets epidemic. Calcium deficiency, linked to the flour, further implicated rising bone and joint tuberculosis mortality among children. Simultaneously, Ireland’s unusually high per-capita institutionalisation of the mentally-ill suggested a health system not fit for purpose, conflicting with Ireland’s desire to appear progressive on the world stage. Heart disease, cancer and senility accounted for half of all deaths but received less attention. This thesis also demonstrates that a key factor in negotiating policy rested with the Health Department’s ability to produce tangible evidence of the increase of disease. Some of these issues were addressed because of wartime aggravation, whereas others reveal the Irish state’s interest in the health of particular populations, especially in that of the youth and the deserving poor, at this time. This research is the first to place health actions and diseases side-by-side. Asking how enthusiasm for addressing one disease might impact efforts to eradicate another gives insight to the balancing act of public health. Then, as now, there is often a tug-of-war between ‘rescue’ and ‘preventative’ measures.